A vacuum cleaner is a device that drives a built-in electric blower fan provided in a housing to create a suction force, uses the suction force to suck up air containing dust or the like foreign materials into the housing, and filters and discharges the sucked air to the outside of the housing through a filter. Such a vacuum cleaner is classified into a canister type, an upright type and a handy type.
U.S. Pat. No. 7,836,548 discloses a “vacuum cleaner” that includes a housing, an electric blower fan, a first filter unit and a second filter unit. The housing includes an air inlet formed in a front bottom of the housing to inhale air, an air outlet formed in a rear outer surface of the housing to discharge air, and an air passage formed to guide air flow between the air inlet and the air outlet. The electric blower fan is placed in the air passage, and includes an electric motor and a fan that is rotated by the electric motor to create a force for sucking up air.
When the electric motor is driven to rotate the fan, air is inhaled through the air inlet and then discharged through the air outlet via the air passage. The first filter unit is arranged in front of the electric blower fan, and filters and collects foreign materials in air. The second filter unit is provided in the rear outer surface of the housing and covers the air outlet, thereby filtering foreign materials in air discharged through the air outlet.